18 research outputs found
WING DIMORPHISM IN TUSCAN POPULATIONS OF RHYZOBIUS LITURA (FABRICIUS) (COLEOPTERA COCCINELLIDAE)
Wing polymorphism is well known among beetle families such as Carabidae, Staphylinidae, Tenebrionidae and Curculionidae, but it is relatively uncommon among Coccinellidae. Rhyzobius litura (Fabricius) is one of the Italian Coccinellidae species, with a dimorphism involving the second pair of wings which may be fully developed (macropterous) or may assume a ribbon-like structure (brachypterous). Specimens of R. litura collected from localities of the Tuscan Archipelago (islands of Elba, Gorgona and Pianosa, Province of Leghorn) and Tuscan hinterland (Lorenzana, San Giuliano and Ponsacco, Province of Pisa) were examined for wing dimorphism. Different sampling techniques were used: Malaise traps, pitfall traps, beating tray, collecting net and visual search. Specimens collected were either adults or larvae, these latter were reared till maturity and then examined. Results showed a remarkable homogeneity within the examined populations, which were always constantly or strongly brachypterous or macropterous. Most of the populations examined were composed of specimens which were brachypterous or with a high level of brachyptery, but the population from the island of Pianosa was entirely composed of macropterous specimens. The hypothesis that the emergence of a long-winged population could be due to geographical isolation is discussed
Prevalence of the microsporidian Nosema ceranae in honeybee (Apis mellifera) apiaries in Central Italy
Nosema ceranae and Nosema apis are microsporidia which play an important role in the
epidemiology of honeybee microsporidiosis worldwide. Nosemiasis reduces honeybee population
size and causes significant losses in honey production. To the best of our knowledge, limited information
is available about the prevalence of nosemiasis in Italy. In this research, we determined the
occurrence of Nosema infection in Central Italy. Thirty-eight seemingly healthy apiaries (2 to 4 hives
each) were randomly selected and screened from April to September 2014 (n= 11) or from May to
September 2015 (n= 27). The apiaries were located in six areas of Central Italy, including Lucca
(n= 11), Massa Carrara (n= 9), Pisa (n= 9), Leghorn (n= 7), Florence (n= 1), and Prato
(n= 1) provinces. Light microscopy was carried out according to current OIE recommendations
to screen the presence of microsporidiosis in adult worker honeybees. Since the morphological characteristics
of N. ceranae and N. apis spores are similar and can hardly be distinguished by optical
microscopy, all samples were also screened by multiplex polymerase chain reaction (M-PCR) assay
based on 16S rRNA-gene-targeted species-specific primers to differentiate N. ceranae from N. apis.
Furthermore, PCR-positive samples were also sequenced to confirm the species of amplified
Nosema DNA. Notably, Nosema spores were detected in samples from 24 out of 38 (63.2%,
95% CI: 47.8–78.5%) apiaries. Positivity rates in single provinces were 10/11, 8/9, 3/9, 1/7, or
1/1 (n= 2). A full agreement (Cohen’s Kappa = 1) was assessed between microscopy and
M-PCR. Based on M-PCR and DNA sequencing results, only N. ceranae was found. Overall,
our results highlighted that N. ceranae infection occurs frequently in the cohort of honeybee
populations that was examined despite the lack of clinical signs. These findings suggest that colony disease outbreaks might result from environmental factors that lead to higher susceptibility of
honeybees to this microsporidian
Ground Beetle (Coleoptera: Carabidae) Assemblages and Slug Abundance in Agricultural Fields Under Organic and Low-Input Conventional Management Within a Long-Term Agronomic Trial in Central Italy
Inside a long-term agronomic trial aimed at evaluating the effects of organic and low-input conventional management systems on soil fertility and arable crop production, we selected six fields bordered by hedgerows, three under each management system. Here, we analyzed the carabid assemblages and the slug abundance. Samplings took place in five different periods, across 1 yr of observations. The carabid abundances were similar in organic and conventional fields. The Shannon–Wiener diversity index (H’) showed a higher value in the conventional fields, although in the organic fields, a higher number of species were observed. The multivariate analysis described similar carabid communities, but excluding the period factor, it showed a significant influence of the management system. There was no difference between the captures of traps placed along the hedgerow and in the middle, whereas in the conventional fields, the hedgerow traps captured a higher number of specimens, showing a role of the hedgerow as carabid reservoir. The slugs were present mainly while green manure was grown on the organic fields where also Poecilus cupreus Linné, 1758 (Coleoptera: Carabidae) was captured abundantly
Who is polluting Italian honey? A filth test survey
Honey is largely considered a natural and healthy product. Investigation on foreign matter in honey provides useful information to evaluate honey quality standards in apiary, honey extraction and packaging phases. Indeed, toxic substances (antibiotics, pesticides and heavy metals) as well as foreign matter (e.g. arthropods, hairs) can contaminate honey, acting as allergens or vectors of human pathogens. We used the filth test to evaluate the presence of foreign matter in samples of Italian honeys, mainly from Tuscany. We revealed a high number of carbon particles and other inorganic fragments, followed by fragments of animal origin. This latter included whole small insects, their cuticular fragments, mites and mammal hairs. The kind of contamination allowed us to evidence uncorrected apicultural practices and to suggest the appropriate corrective measures. The filth test method is an excellent and cheap tool to check honey quality, requiring minimal instrumental equipment and giving results that can be interpreted quickly